Combined fan and cooling device using the same

ABSTRACT

A combined fan for cooling a heat source includes a hub and multiple blades. The hub has a first side and a second side opposite to each other. The blades are distributed along an outer circumferential surface of the hub, and each of the blades includes a first part extending from the hub and a second part connected to the first part. Each of the second parts protrudes beyond the first side or the second side, and each of the second parts is formed by multiple strip structures. Therefore, each of the strip structures can be closer to a surface of the heat source to dissipate the heat more effectively.

TECHNICAL FIELD

The present invention relates to a fan and a cooling device using the same and, in particular, to a combined fan and a cooling device using the same while combining strip structures to be closer to a heat source.

BACKGROUND

With the development in the electronic industry, the electronic component has enhanced performance and the chip set inside provides a faster computing speed. Due to the increase in the computing speed and the increase in the number of chips, the amount of heat generated by the chips during operation also increases. If the heat is not dissipated away in time, it will greatly compromise the performance of the electronic component and lower the computing speed of the electronic component. Moreover, the heat accumulation can result in malfunction and damage of the electronic component, so heat dissipation is required for the electronic component.

In a desktop computer or a notebook which has a limited installation space, a fan device is usually installed near the electronic component. The airflow generated by rotation of the blades in the fan device directly blows to the electronic component or to the heat sink installed on the electronic component to thereby dissipate heat. The conventional fan structure normally includes a hub and multiple blades extending outward linearly from the hub. The blades are disposed tilted along the same rotation direction. The magnitude of the airflow generated by the fan device depends on the rotation speed of the blades and also depends on the swept area and the angle of the blades.

However, the conventional design in the swept area and the angle of the blades cannot improve the heat dissipation effectively. Accordingly, the inventor made various studies to solve the above-mentioned problems, on the basis of which the present invention is accomplished.

SUMMARY

It is an object of the present invention to provide a combined fan and a cooling device using the same, wherein strip structures are incorporated in order to be closer to a surface of the heat source to thereby dissipate the heat more effectively.

Accordingly, the present invention provides a combined fan for cooling a heat source. The combined fan comprises a hub and multiple blades. The hub has a first side and a second side opposite to each other. The blades are distributed along an outer circumferential surface of the hub, and each of the blades includes a first part extending from the hub and a second part connected to the first part, wherein each of the second parts protrudes beyond the first side or the second side, and each of the second parts is formed by a plurality of strip structures.

Accordingly, the present invention provides a cooling device for cooling a heat source, comprising the combined fan of the foregoing embodiment and a housing. The housing receives the combined fan, and each of the second parts is disposed toward the heat source.

The present invention further has the following features. Each of the blades is closer to the heat source by utilizing the feature that the second part (i.e. the strip structures) has better flexibility than the first part, so that the waste heat of the heat source can be dissipated away more effectively. The strip structures can be independently attached to and protrude beyond one side surface of each of the blades (i.e. the first part), or the strip structures can be combined with a joining portion to become a brush device which can be assembled to the side surface of each of the blades easily and conveniently.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will become more fully understood from the detailed description and the drawings given herein below for illustration only, and thus does not limit the disclosure, wherein:

FIG. 1 is a perspective view illustrating a combined fan according to the first embodiment of the present invention;

FIG. 2 is a perspective view illustrating the combined fan according to another embodiment of the present invention;

FIG. 3 is a perspective exploded view of the present invention, illustrating that the combined fan of the first embodiment is used in a cooling device;

FIG. 4 is a cross-sectional view of the present invention, illustrating that the combined fan of the first embodiment is used in the cooling device;

FIG. 5 is a perspective exploded view of the present invention, illustrating that the combined fan of a second embodiment is used in the cooling device; and

FIG. 6 is a perspective view illustrating the combined fan according to still another embodiment of the present invention.

DETAILED DESCRIPTION

Detailed descriptions and technical contents of the present invention are illustrated below in conjunction with the accompany drawings. However, it is to be understood that the descriptions and the accompany drawings disclosed herein are merely illustrative and exemplary and not intended to limit the scope of the present invention.

Referring to FIG. 1 and FIG. 2, the present invention provides a combined fan 100 comprising a hub 110 and a plurality of blades 150. The hub 110 has a first side 120 and a second side 130 opposite to each other. The blades 150 are distributed equidistantly or not along an outer circumferential surface 140 of the hub 110, and each of the blades 150 includes a first part 160 extending from the hub 110 and a second part 170 connected to the first part 160, wherein each of the second parts 170 protrudes beyond the first side 120 or the second side 130, and each of the second parts 170 is preferably formed by a plurality of strip structures 180.

In the present embodiment, each of the blades 150 is preferably arranged at an angle and extends linearly toward the same rotation direction, for being applied in a centrifugal flow fan. Alternatively, each of the blades 150 can be curved outwardly from the outer circumferential surface 140 of the hub 110, for being applied in, for example, an axial flow fan, as shown in FIG. 4. However, in other different embodiments, the blades 150 can be arranged radially or can extend curvedly or can be blades in other forms; the present invention is not limited in this regard.

In the embodiment shown in FIGS. 1 and 2, the hub 110 includes a rotation shaft 112 and a recess 114. One end of the rotation shaft 112 is preferably connected to a bottom of the second side 130 and is disposed in the center of the recess 114. Therefore, each of the second parts 170 preferably protrudes in a direction opposite to the direction in which the recess 114 opens, i.e. protruding outwardly beyond the second side 130. However, in another embodiment, one end of the rotation shaft 112 can be connected to a bottom of the first side 120, so that the second part 170 protrudes outwardly beyond the first side 120; the configuration may vary as required.

Furthermore, the material of each of the strip structures 180 of each second part 170 preferably includes, but is not limited to, graphite, metal or other flexible heat-conductive material. The shape of each strip structure 180 can be, but not limited to, a fiber or a wire, e.g. a graphite fiber, a copper wire, an aluminum wire, or an alloy wire thereof. Each of the first parts 160, which is part of the body of the combined fan 100, is of greater rigidity than the rigidity of each of the second parts 170. That is to say, each of the second parts 170 is of greater flexibility than each of the first parts 160, so the strip structure 180 changes shape with respect to the first part 160, thereby increasing a swept area and enhancing the wind blowing effect.

The embodiment shown in FIG. 1 further includes a plurality of brush devices 190, and each of the brush devices 190 is combined with each of the second parts 170 and fixedly attached to one side surface of each of the blades 150. Each of the brush devices 190 further includes a joining portion 192 for combining and fixing each of the strip structures 180, and the joining portion 192 is made from the same or a different metal material from the material of each strip structure 180. To accelerate heat dissipation, each of the first parts 160 and each of the brush devices 190 can be made from the same or a different heat-conductive material, such as copper, silver, aluminum, or alloy thereof the material may vary as required. However, in the embodiment shown in FIG. 2, each of the second parts 170 can also be directly fixedly attached to one side surface of each of the blades 150; the configuration may vary as required.

Furthermore, in another embodiment, each of the first parts 160 is integrally formed with each of the second parts 170. Alternatively, in still another embodiment, each of the second parts 170 and each of the first parts 160 can be formed by an insert-molding method; this may vary as required.

Please refer to FIGS. 3 and 4 which are a perspective exploded view and a cross-sectional view of the present invention, illustrating that the combined fan is used in the cooling device according to the first embodiment. As shown in the drawings, the present invention further provides a cooling device 200 for cooling a heat source 210. The cooling device 200 comprises a combined fan 100 of the foregoing embodiment and a housing 220. The housing 220 receives the combined fan 100, and each of the second parts 170 is disposed toward the heat source 210.

In the present embodiment, the housing 220 is preferably made from metal having good heat conductivity, such as iron, aluminum or alloy thereof. The housing 220 includes a first outer case 230 and a second outer case 240 covering the first case 230. The first outer case 230 has a suspension shaft 250 and at least one air inlet 260. When the first outer case 230 covers the second outer case 240, an air outlet 270 is formed at one side of the housing 220, so the at least one air inlet 260 is in a direction perpendicular or corresponding to the direction of the air outlet 270, and accordingly the combined fan 100 in the present embodiment is preferably a centrifugal flow fan.

The hub 110 of the combined fan 100 has a rotation shaft 112, for assembly with the suspension shaft 250 and has a recess 114 for accommodating a stator (not illustrated). One end of the rotation shaft 112 is preferably connected to a bottom of the second side 130 and is disposed in the center of the recess 114, so the combined fan 100 rotates about the suspension shaft 250 as center with respect to the housing 220.

Referring to FIG. 4, when the cooling device 200 is in contact with a surface of the heat source 210 electrically connected to a circuit board 212, the second outer case 240 is in contact with the surface of the heat source 210, and each of the second parts 170 (i.e. the strip structures 180) is disposed toward the heat source 210. When the cooling device 200 is in operation, the centrifugal flow fan 100 not only provides airflow generated by rotation of the blades 150, but also dissipates away the waste heat from the air outlet 270 more quickly and effectively by disposing the strip structures 180 in a manner closest to the heat source 210.

In the present embodiment, each of the second parts 170 is preferably not in contact with an inner surface of the second outer case 240 of the housing 220, i.e there is a very tiny gap D between each strip structure 180 and the inner surface of the second outer case 240. Therefore, each strip structure 180 does not contact the inner surface of the second outer case 240, thereby preventing noises, abrasion or other interference. However, in other embodiment, since each second part 170 can be made from a soft material, so each second part 170 can contact the inner surface of the second outer case 240 of the housing 220 to achieve the same effect mentioned above.

Please refer to FIG. 5 which is a perspective exploded view of the present invention, illustrating that the combined fan is used in the cooling device according to the second embodiment. In the present embodiment, the single one housing 220 includes at least one air inlet 260 and an air outlet 270, wherein the air outlet 270 is disposed corresponding to the at least one air inlet 260, so the combine fan 100 having the curved blades 150 can be assembled onto the suspension shaft 250 of the housing 220 via the air outlet 270. In the present embodiment, the combined fan 100 is preferably an axial flow fan.

When the cooling device 200 of the present embodiment is disposed close to the surface of the heat source (not illustrated), each strip structure 180 is disposed more directly toward the heat source. Similarly, when the cooling device 200 is in operation, each strip structure 180 of the axial flow fan 100 is disposed in a manner closest to the surface of the heat source so as to dissipate away the waste heat of the heat source from the air outlet 270, thereby enhancing heat dissipation.

Furthermore, in the embodiment shown in FIG. 5, there is a very tiny gap D between each second part 170 and the heat source (not illustrated), so each strip structure 180 does not contact the surface of the heat source, thereby avoiding noises or abrasion. Certainly, in other embodiment, since each of the second parts 170 is made from a soft material, so each second part 170 can also contact the surface of the heat source; this may vary as required.

Please refer to FIG. 6 which is a perspective view illustrating the combined fan according to still another embodiment of the present invention. As shown in FIG. 6, besides being disposed toward the heat source, the second part 170 can also be disposed at an outer edge of the first part 160. The second part 170 is combined with the first part 160 by an insert-molding method. Other descriptions relating to the structure and connection relationship of the second part 170 according to the present embodiment are provided above, and thus are not repeated herein.

Each of the blades 150 can be closer to the heat source 210 by utilizing the feature that each second part 170 (i.e. the strip structures 180) has better flexibility than the first part 160, so that the waste heat of the heat source 210 can be dissipated away more effectively. Furthermore, the strip structures 180 can be independently attached to and protrude from one side surface of each of the blades 150 (i.e. the first part 160), or the strip structures 180 can be combined with a joining portion 192 to become a brush device 190 which can be assembled to the side surface of each of the blades 150 more easily and conveniently.

It is to be understood that the above descriptions are merely the preferable embodiments of the present invention and are not intended to limit the scope of the present invention. Equivalent changes and modifications made in the spirit of the present invention are regarded as falling within the scope of the present invention. 

What is claimed is:
 1. A combined fan, comprising: a hub including a first side and a second side opposite to each other; and a plurality of blades, each of the blades being distributed along an outer circumferential surface of the hub, each of the blades including a first part extending from the hub and a second part connected to the first part, wherein each of the second parts protrudes beyond the first side or the second side, and each of the second parts is formed by a plurality of strip structures.
 2. The combined fan of claim 1, wherein the material of each of the strip structures includes graphite or metal.
 3. The combined fan of claim 1, wherein each of the first parts is of greater rigidity than the rigidity of each of the second parts.
 4. The combined fan of claim 1, wherein each of the first parts is integrally formed with each of the second parts.
 5. The combined fan of claim 1, wherein each of the second parts and each of the first parts are formed by an insert-molding method.
 6. The combined fan of claim 1, further comprising a plurality of brush devices, each of the brush devices being combined with each of the second parts and fixedly attached to one side surface of each of the blades.
 7. The combined fan of claim 6, wherein each of the brush devices further includes a joining portion for combining and fixing each of the strip structures.
 8. A cooling device for cooling a heat source, comprising: a combined fan including: a hub having a first side and a second side opposite to each other; and a plurality of blades, each of the blades being distributed along an outer circumferential surface of the hub, and each of the blades including a first part extending from the hub and a second part connected to the first part, wherein each of the second parts protrudes beyond the first side or the second side, and each of the second parts is formed by a plurality of strip structures; and a housing receiving the combined fan, each of the second parts being disposed toward the heat source.
 9. The cooling device of claim 8, wherein the material of each of the strip structures includes graphite or metal.
 10. The cooling device of claim 8, wherein each of the first parts is of greater rigidity than the rigidity of each of the second parts.
 11. The cooling device of claim 8, wherein each of the first parts is integrally formed with each of the second parts.
 12. The cooling device of claim 8, wherein each of the second parts and each of the first parts are formed by an insert-molding method.
 13. The cooling device of claim 8 further including a plurality of brush devices, and each of the brush devices being combined with each of the second parts and fixedly attached to one side surface of each of the blades.
 14. The cooling device of claim 13, wherein each of the brush devices further includes a joining portion for combining and fixing each of the strip structures.
 15. The cooling device of claim 8, wherein the housing includes a first outer case, a second outer case covering the first outer case, and an air outlet, the first outer case has a suspension shaft and at least one air inlet, the at least one air inlet is in a direction perpendicular or corresponding to the direction of the air outlet.
 16. The cooling device of claim 8, wherein one side surface of the housing is attached to a surface of the heat source, each of the strip structures is in contact with or in non-contact with the housing or the surface of the heat source, when each of the strip structures is in non-contact with the housing or the surface of the heat source, a gap is formed between each of the strip structures and the housing or between each of the strip structures and the surface of the heat source. 